正压送风防烟在地铁车站应用的模拟分析  

A numerical simulation model of a pressurized smoke-removable air supply system in a subway station

作　　者：梁强[1] 魏东[1] 

机构地区：[1]中国人民武装警察部队学院消防指挥系,河北廊坊065000

出　　处：《安全与环境学报》2011年第4期226-230,共5页Journal of Safety and Environment

基　　金：公安部部级科研项目(20049461201)

摘　　要：设定两种场景,利用大涡场模拟软件FDS对某双层岛式车站站台火灾进行数值模拟,探讨正压送风防烟在地铁车站内的应用。模拟获得双层岛式地铁车站火场烟气的蔓延过程以及站台通向站厅楼梯口处的气流分布,证明利用正压送风可以保证该处气流方向和流速,各参数满足规范要求,可以为人员疏散提供便利条件。This paper is inclined to introduce a numerical simulation model of a pressurized smoke-removable air supply system in a sub-way station developed by the present authors. As is known, subway stations are a plaee usually congested with large crowds. Any large-scale fire accidents, once taking place, would involve serious human casualties as well as material damages. For this purpose, the present paper intended to develop a LES field simulation software FDS to simulate some sorts of fire accidents in an Island-platform of doubledecked subway station. In order to test the applicability of a pressurized air supply system in the subway stations, two scenes were laid out for our purpose of simulation. Based on the common smoke-removing theory, the pressurized air curtain system has been set up at the top of the stairs so as to create air curtain with an air-current flowing at a speed of 7 m/s, and another air-current flowing at an angle of 45° from top to bottom. The process of smoke movement in the station and the vector diagram of the velocity at stairs were obtained during the simulation. The results of our simulation demonstrate that the air supply amount calculated based on the accounting code would not be enough for the control of the high-temperature smoke through the stairs for 10 MW fires. In addition, the cold air strength cannot yet overwhelm the hot smoke current caused by the buoyancy, because the smoke flu velocity at the moment may reach 1.2 m/s. If creating an air curtain at the top of stairs, it would be possible to make the airflow velocity and direction adapted to the needs of the Code of the subway design. In such cases, the direction of the airflow may just be opposite to the crowd of residents around. Besides, since the downward flow speed can be greater than 1.5 m/s but on the wall of stair, the flow speed can be as high as 0.7 - 1.0 m/s, with the rest parts in the building, the speed are above 2.1 m/s. At the center of stair the flow speed is the highest which can reach about 4 m/s. T

关 键 词：安全工程 地铁火灾 数值模拟 正压送风系统 气流组织 

分 类 号：X932[环境科学与工程—安全科学]